Intramolecular Dearomatizing [3 + 2] Annulation of α-Imino Carbenoids with Aryl Rings Furnishing 3,4-Fused Indole Skeletons
摘要:
The rhodium-catalyzed dearomatizing [3 + 2] annulation reaction of 4-(3-arylpropyl)-1,2,3-triazoles is described. It provides a straightforward synthetic pathway from simple 5-aryl-1-alkynes leading to tricyclic 3,4-fused dihydroindoles via the corresponding 1,2,3-triazoles.
A Rh-catalyzed asymmetric intramolecular Buchner ring expansion of α-alkyl-α-diazoesters has been developed. The present protocol generates a 5,7-fused ring system in an enantioselective manner while minimizing β-hydrogen migration, which has been a competing reaction when using α-alkyl-α-diazoesters. The ester functionality at the bridgehead position would be a useful synthetic handle for further